Abstract

In this paper I examine a cognitive mechanism of incommensurability. Using the frame model of concept representation to capture structural relations within concepts, I reveal an ontological difference between object and event concepts: the former are spatial but the latter temporal. Experiments from cognitive sciences further demonstrate that the mind treats object and event concepts differently. Thus, incommensurability can occur in conceptual change across different ontological categories. I use a historical case to illustrate how the ontological difference between an object and an event concept actually caused incommensurability in the context of nineteenth‐century optics. The cognitive and historical analyses indicate that incommensurability can be a local phenomenon and does not necessarily imply incomparability.